surging pump

Discussion in 'Irrigation' started by sonny steele, Mar 11, 2006.

  1. sonny steele

    sonny steele LawnSite Member
    Messages: 11

    I installed an irrigation system for a customer she already has a 2 inch stayright lawn pump that has been there for at least 2 years, I tested my first zone when I got finished with it, I only have eight sprinklers on this zone 2.0 gallons each the pump acts like it is surging I can close off three pop ups and my pressure is fine could the impellar be bad or do you think I have well issues
  2. Jason Rose

    Jason Rose LawnSite Fanatic
    Messages: 5,858

    Ok, you don't know the horsepower of the pump? The flow rate GPM? (at operating pressure).

    A 2 inch pump, suction or discharge, would be prolly like a 2 horse and could be capable of 40+ GPM.

    more info please!
  3. Dirty Water

    Dirty Water LawnSite Fanatic
    Messages: 6,794

    Is the pump surging, or is it cylcing? Cycling is caused if you are not using enough water from it. This is causing the pressure to build up and its shutting off the pressure switch.

    You said your first zone used 8 rotors with 2 GPM nozzles? So you are using 16 GPM out of a possible 40 or so (You should find out its exact output before you start next time).

    Try bumping up the nozzle size and see if that helps the situation, if you absolutely cannot get the pump to stop cycling, you could set it up to run off a pump start relay (Wire a pressure switch in series with the relay as a fail safe).

    Some people have installed a nifty device called a Cycle Stop Valve...I've never needed one, so I have no experience on it.

Share This Page